What setting locks local rotation and scaling of an object?
It sounds like you have activated the Manipulate Pivot Points tool.  It's found directly to the right of the Pivot Point selection menu in 3D view > Header.

Here's a demo.



It can also be toggled with &#9095; Alt, (comma).

Now, if you mistakenly press some keyboard shortcut that ends up causing you grief like this; you can try pulling down the top header bar to view the Info area.  It should contain most of what you've recently done.(to view EVERYTHING you'd have to enable debug logging, that's gets messy quickly)